66 ASTEROIDEA. 
do not extend far into the rays, are closely covered with sharp 
spiniform granules. The marginals are short but quite distinct, 
and the superomarginals, though much less wide than the infero- 
marginals, remain distinct to the top of the arm. They are both 
covered by large granular plates, which sometimes take on the 
appearance of spines; there are from 20 to 40 marginals on either 
side of each arm. The dorsal surface formed of the ends of fine 
paxille, the form of which is obscured by the integument which 
invests them. 
Colour: dry or in spirit, white ; alive, cinnabar to orange. 
Breadth of arm 
R. tr. at base. 
See 8 i 
1S) Fi eed 
Distribution. East and western sides of northern part of Atlantic 
to Arctic Ocean. 20-690 fms. 
a, b. Faeroe Channel, 1312 fms. ‘ Porcupine’ Exp. (St. 82). 
c,d. Between Faeroe and Shetland, 640 fms. ‘ Porcupine’ Exp. (St. 65). 
2. ASTROPECTEN. 
Astropecten, C. F. Schultze, Betrachtung versteiner. Seesterne, (1760) 
p- 50; Gray, Ann. § Mag. vi. (1840) p. 180; M. Tr. Syst. Ast. 
(1842) p. 67 ; Norm. Ann. & Mag. xv. (1865) p. 115; Perr. Arch. Zool. 
exp. iv. (1875) p. 3802; Viguier, op. cit. vii. (1878) p. 251; Sladen, 
Chall. Rep. Ast. 1889, p. 175. 
Stellaria, Nardo (non Moller), Isis, 1834, p. 716. 
Asterias, Ag. (non Linn.), Mém. Soc. Neuch. i. (1836) p. 191; Forbes, 
Mem. Wern. Soe. viii. (1839) p. 118; M. Tr. Arch. f. Nat. 1840, 
. 323. 
Crenaster, d’Orb. Prodi. Pal. i. (1849) p. 240. 
An Astropectinine in which there is no webbed marginal fringe ; 
the superomarginal plates have a prominent ridge, all the marginals 
are more or less quadrate in form, and those of the upper series are 
nearly of the same size as those of the lower. 
Key to the Species. 
Marginals with rectangular sides 
We eee os 1. A. arregularis. 
Marginals wedge-shaped 
sil este ofall taes rele 2. A. sphenoplax. 
1. Astropecten irregularis. 
Asterias irregularis, Penn. Brit. Zool. iv. (1777) p. 52, no, 57. 
Astropecten irregularis, Gray, Ann. § Mag. vi. (1840) p. 182; 1d. 
Brit. Rad. (1848) p. 18; Duy. § Hup. Ech, (1862) p. 414; 
Norman, Ann. & Mag. xv. (1865) p. 116; Hodge, Tr. Northumb. 
& Durh. iv. (1872) p. 183; Perr. Arch. Zool. v. (1876) p. 288 ; 
Kor. §& Dan. Norske Nordhavs Asteroidea, (1884) p. 82; Sladen, 
Chall. Rep. Ast. (1889) p. 209. 
